lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 01 Aug 2013 22:27:13 +0200
From:	"Rafael J. Wysocki" <rjw@...k.pl>
To:	Tang Chen <tangchen@...fujitsu.com>
Cc:	lenb@...nel.org, tglx@...utronix.de, mingo@...e.hu, hpa@...or.com,
	akpm@...ux-foundation.org, tj@...nel.org, trenn@...e.de,
	yinghai@...nel.org, jiang.liu@...wei.com, wency@...fujitsu.com,
	laijs@...fujitsu.com, isimatu.yasuaki@...fujitsu.com,
	izumi.taku@...fujitsu.com, mgorman@...e.de, minchan@...nel.org,
	mina86@...a86.com, gong.chen@...ux.intel.com,
	vasilis.liaskovitis@...fitbricks.com, lwoodman@...hat.com,
	riel@...hat.com, jweiner@...hat.com, prarit@...hat.com,
	zhangyanfei@...fujitsu.com, yanghy@...fujitsu.com, x86@...nel.org,
	linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org, linux-acpi@...r.kernel.org
Subject: Re: [PATCH v2 04/18] acpi: Introduce acpi_invalid_table() to check if a table is invalid.

On Thursday, August 01, 2013 03:06:26 PM Tang Chen wrote:
> In acpi_initrd_override(), it checks several things to ensure the
> table it found is valid. In later patches, we need to do these check
> somewhere else. So this patch introduces a common function
> acpi_invalid_table() to do all these checks, and reuse it in different
> places. The function will be used in the subsequent patches.
> 
> Signed-off-by: Tang Chen <tangchen@...fujitsu.com>
> Reviewed-by: Zhang Yanfei <zhangyanfei@...fujitsu.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>

> ---
>  drivers/acpi/osl.c |   86 +++++++++++++++++++++++++++++++++++++---------------
>  1 files changed, 61 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
> index 91d9f54..8df8a93 100644
> --- a/drivers/acpi/osl.c
> +++ b/drivers/acpi/osl.c
> @@ -572,9 +572,68 @@ static const char * const table_sigs[] = {
>  /* Must not increase 10 or needs code modification below */
>  #define ACPI_OVERRIDE_TABLES 10
>  
> +/*******************************************************************************
> + *
> + * FUNCTION:    acpi_invalid_table
> + *
> + * PARAMETERS:  File               - The initrd file
> + *              Path               - Path to acpi overriding tables in cpio file
> + *              Signature          - Signature of the table
> + *
> + * RETURN:      0 if it passes all the checks, -EINVAL if any check fails.
> + *
> + * DESCRIPTION: Check if an acpi table found in initrd is invalid.
> + *              @signature can be NULL. If it is NULL, the function will check
> + *              if the table signature matches any signature in table_sigs[].
> + *
> + ******************************************************************************/
> +int __init acpi_invalid_table(struct cpio_data *file,
> +			      const char *path, const char *signature)
> +{
> +	int idx;
> +	struct acpi_table_header *table = file->data;
> +
> +	if (file->size < sizeof(struct acpi_table_header)) {
> +		INVALID_TABLE("Table smaller than ACPI header",
> +			      path, file->name);
> +		return -EINVAL;
> +	}
> +
> +	if (signature) {
> +		if (memcmp(table->signature, signature, 4)) {
> +			INVALID_TABLE("Table signature does not match",
> +				      path, file->name);
> +			return -EINVAL;
> +		}
> +	} else {
> +		for (idx = 0; table_sigs[idx]; idx++)
> +			if (!memcmp(table->signature, table_sigs[idx], 4))
> +				break;
> +
> +		if (!table_sigs[idx]) {
> +			INVALID_TABLE("Unknown signature", path, file->name);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	if (file->size != table->length) {
> +		INVALID_TABLE("File length does not match table length",
> +			      path, file->name);
> +		return -EINVAL;
> +	}
> +
> +	if (acpi_table_checksum(file->data, table->length)) {
> +		INVALID_TABLE("Bad table checksum",
> +			      path, file->name);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>  void __init acpi_initrd_override(void *data, size_t size)
>  {
> -	int sig, no, table_nr = 0, total_offset = 0;
> +	int no, table_nr = 0, total_offset = 0;
>  	long offset = 0;
>  	struct acpi_table_header *table;
>  	char cpio_path[32] = "kernel/firmware/acpi/";
> @@ -593,33 +652,10 @@ void __init acpi_initrd_override(void *data, size_t size)
>  		data += offset;
>  		size -= offset;
>  
> -		if (file.size < sizeof(struct acpi_table_header)) {
> -			INVALID_TABLE("Table smaller than ACPI header",
> -				      cpio_path, file.name);
> -			continue;
> -		}
> -
>  		table = file.data;
>  
> -		for (sig = 0; table_sigs[sig]; sig++)
> -			if (!memcmp(table->signature, table_sigs[sig], 4))
> -				break;
> -
> -		if (!table_sigs[sig]) {
> -			INVALID_TABLE("Unknown signature",
> -				      cpio_path, file.name);
> +		if (acpi_invalid_table(&file, cpio_path, NULL))
>  			continue;
> -		}
> -		if (file.size != table->length) {
> -			INVALID_TABLE("File length does not match table length",
> -				      cpio_path, file.name);
> -			continue;
> -		}
> -		if (acpi_table_checksum(file.data, table->length)) {
> -			INVALID_TABLE("Bad table checksum",
> -				      cpio_path, file.name);
> -			continue;
> -		}
>  
>  		pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
>  			table->signature, cpio_path, file.name, table->length);
> 
-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists